Toronto Wastewater Treatment Works

The Toronto Wastewater Treatment Works serves the area from Teralba to Wangi Wangi on the western side of Lake Macquarie, including the townships of Marmong Point, Bolton Point, Toronto and Rathmines.

It currently treats 6 megalitres per day and can handle wastewater from a population of up to 42,000 people.


Toronto Wastewater Treatment Works provides secondary treatment of the wastewater and is designed to remove nutrients (nitrogen and phosphorus) and offer some disinfection.

It provides secondary treatment of the wastewater by the following process:

  1. the effluent receives screening, flow measurement and odour control at the inlet works followed by biological treatment in two extended aeration tanks.
  2. treated effluent is drawn off to a catch pond before it is discharged.
  3. waste mixed liquor is thickened on a gravity drainage deck and dewatered through a filter belt press in the biosolids handling facility.

Recycling and reuse

The biosolids produced at the plant are beneficially used for mine site rehabilitation.

All treated effluent is discharged via the Lake Macquarie Crossing to the Belmont ocean outfall.

Environment Protection Authority pollution monitoring

Pollution monitoring data is collected by Hunter Water, as required under the Environment Protection Licences (EPL) issued by the NSW Environment Protection Authority (EPA). Read more about the EPL at